Abstract
The paper is devoted to recent results concerning investigation of physical processes occurring in a “laser greenhouse” target. Results of experimental and theoretical studies of laser-pulse interaction with a low-density absorber of the target, namely, with a porous substance having density close to the plasma critical density, are presented. On the basis of a vast cycle of experiments carried out in a number of laboratories, it is shown that the absorption of the laser radiation in porous media, including those with a density exceeding the critical one by at least a factor of 4 to 6, has a bulk nature and is distributed over the target depth. In particular, the laser-radiation absorption region in a porous substance with density 10−3–10−2 g/cm3 is extended into the target 400–100 μm, respectively. The coefficient of absorption of laser radiation with intensity 1014–1015 W/cm2 in porous substances, including those of the supercritical density, is 70–90%. Experiments have not shown enhanced (compared to a solid-state target) radiation intensity associated with a possible development of parametric instabilities in an extended laser plasma of low-density porous media, as well as noticeable contribution of fast electrons to the energy balance and their effect on the energy transfer. In this paper, theoretical models are developed explaining features of the laser-radiation absorption and energy transfer in porous media. These models are based on the phenomenon of laser-radiation interaction with solid components of a porous substance and plasma production inside pores and cells of the medium. The efficiency of energy conversion in the vicinity of the ignition threshold for the laser-greenhouse target is investigated in the case of an absorber having the above properties. Numerical calculations have shown that a thermonuclear-gain coefficient of 1 to 2 (with respect to the energy absorbed) is attained for a laser-radiation energy of 100 kJ.
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References
Yu. V. Afanas'ev, N. G. Basov, P. P. Volosevich, et al.Pis'ma Zh. Éksp. Teor. Fiz.,21, 159 (1975); “High-energy-gain targets for laser thermonuclear fusion,” in:Proceedings of the 5th International Conference on Plasma Physics and Controlled Nuclear-Fusion Research (November 11–15, 1974, Tokyo), IAEA, Vienna (1975), Vol. II, p. 559.
J. Nickolls, J. Lindl, W. Mead, et al., “Laser-driven implosion of hollow pellets”, in:Proceedings of the 5th International Conference on Plasma Physics and Controlled Nuclear-Fusion Research (November 11–15, 1974, Tokyo), IAEA, Vienna (1975), Vol. II, p. 535.
V. Rozanov, M. Decroisette, S. Gus'kov, et al.. “Inertial confinement target physics”, in: W. J. Hogan (ed.),Energy from Inertial Fusion, IAEA, Vienna (1975), Chapter II, p. 21.
S. Weber, S. Dalhed, D. Eimerl, et al.,XXV Anomalous Absorption Conference (Aspen, Colorado, USA, May 28–June 1, 1995), p. 88.
T. R. Ditrich, S. W. Haan, M. M. Marinak, et al.,Book of Abstracts of the XXV European Conference on Laser Interaction with Matter (May 4–8, 1998, Formia, Italy), p. 105.
S. W. Haan, S. M. Pollaine, J. Lindl, et al.,Phys. Plasmas,2, 2480 (1995); J. Lindl, Preprint LLNL UCRL-JC119015 (1995).
S. Yu. Gus'kov and V. B. Rozanov, “Thermonuclear greenhouse target”, in:Book of Abstracts for the National Conference on Plasma Physics and Controlled Fusion (Zvenigorod, Russia, 1994).
S. Yu. Gus'kov, N. V. Zmitrenko, and V. B. Rozanov,Zh. Éksp. Teor. Fiz.,108, 548 (1995) [JETP,81, 296 (1995)].
A. A. Samarskii, S. A. Gaifulin, A. V. Zakharov, et al., in:Problems of Atomic Science and Technology: Methods and Codes for Numerical Solution of Problems of Mathematical Physics [in Russian], Énergoatomizdat, Moscow (1983), No. 2, p. 38.
G. A. Vergunova and V. B. Rozanov, “Calculation of target compression with account for plasma self-radiation”, in: S. J. Rose (ed.),Laser Interaction with Matter, Proceedings of the 23rd European Conferens on Laser Interaction with Matter (Oxford, UK, 1994). IOP Publishing, Bristol, Ser. No. 140 (1995), p. 447.
S. Yu. Gus'kov and V. B. Rozanov,Kvantovaya Électron.,24, 715, (1997) [Quantum Electron.,27, 696 (1997)].
S. Yu. Gus'kov, A. Caruso, V. B. Rozanov, and C. Strangio, “Experimental observation of an anomalously high absorption of laser radiation in laser-produced plasma of supercritical density foam”, in:Book of Abstracts of the XXV Zvenigorod Conf. on Plasma Physics and Controlled Fusion (Zvenigorod, 2–6 March, 1998). Izd Mos. Fiz. Obshchestva, Moscow (1998), p. 100.
A. E. Bugrov, S. Yu. Gus'kov, V. B. Rozanov, et al.,Zh. Éksp. Teor. Fiz. 111, 903 (1997) [JETP,84, 497 (1997)].
A. Caruso, S. Yu. Gus'kov, N. N. Demchenko, et al.,J. Russ. Laser Res.,18, 464 (1997).
A. E. Bugrov, I. N. Burdonskii, V. V. Gavrilov, et al.,Zh. Éksp. Teor. Fiz.,115, 805, (1999) [JETP,88, 441 (1999)].
N. G. Basov, S. Yu. Gus'kov, G. V. Danilova, et al.,Kvantovaya Élektron.,12, 1289 (1985).
A. E. Danilov, N. N. Demchenko, V. B. Rozanov, et al.,Kvantovaya Élektron. 4, 1034 (1977).
W. W. Simmons, “Simple analytic solution for uniform irradiation of spherical targets”, in: M. Andre and H. T. Powell (Eds.),Proceedings of the First Annual International Conference on SSLA, Proc. SPIE,2663, 249 (1995).
V. B. Rozanov and N. N. Demchenko,Kvantovaya Élektron.,12, 1895 (1985).
S. Yu. Gus'kov, V. V. Demchenko, I. G. Lebo, et al.,J. Russ. Laser Res.,19, 397 (1998).
I. G. Lebo, I. V. Popov, V. B. Rozanov, et al.,Kvantovaya Élektron. 22, 1257 (1995).
V. N. Derkach, S. V. Bondarenko, S. G. Garanin, et al., “Research directed to the development of methods of spatial and temporal smoothing of high-power laser beams”, in:Book of Abstracts of the XXV Europian Conference on Laser Interaction with Matter (May 4–8, 1998, Formia, Italy).
S. Yu. Gus'kov, Yu. S. Kas'yanov, M. O. Koshevoi, et al.,Pis'ma Zh. Éksp. Teor. Fiz.,64, 462 (1996) [Pis'ma JETP,64, 502 (1996)].
S. Yu. Gus'kov, Yu. S. Kas'yanov, M. O. Koshevoi, et al..Laser and Particle Beams,17, 287 (1999).
V. V. Nikishin, V. F. Tishkin, I. V. Popov, et al.,Mat. Model.,7, 5 (1999).
S. Yu. Gus'kov and V. B. Rozanov, “Physics of laser greenhouse targets: review of experimental and theoretical results”, in: G. Velarde, J. M. Martinez-Val, E. Minguez and J. M. Perlado (eds.),Proceedings of the XXIV Europian Conference on Laser Interaction with Matter (Madrid, 1996), World Scientific, Singapore (1997).
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Translated from Preprint No. 58 of the P. N. Lebedev Physical Institute, Moscow (1999).
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Caruso, A., Demchenko, N.N., Demchenko, V.V. et al. Physical processes in a laser-greenhouse target: Experimental results, theoretical models, and numerical calculations. J Russ Laser Res 21, 335–369 (2000). https://doi.org/10.1007/BF02515358
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DOI: https://doi.org/10.1007/BF02515358